Note
Go to the end to download the full example code.
Ship drift
from datetime import datetime
from opendrift.models.shipdrift import ShipDrift
o = ShipDrift(loglevel=20)
o.add_readers_from_list([
'https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml',
'https://thredds.met.no/thredds/dodsC/mepslatest/meps_lagged_6_h_latest_2_5km_latest.nc',
'https://thredds.met.no/thredds/dodsC/cmems/mywavewam3km/dataset-wam-arctic-1hr3km-be.ncml'
])
09:44:13 INFO opendrift:576: OpenDriftSimulation initialised (version 1.14.7 / v1.14.7-21-gb739e9e)
Seed ship elements at defined position and time Note: beam/length ratio is larger than allowed, but is then clipped internally
o.seed_elements(lon=5.0, lat=63.0, radius=1000, number=1000,
time=datetime.now(),
length=80.0, beam=20.0, height=9.0, draft=4.0)
09:44:13 WARNING opendrift.models.shipdrift:181: Ratio of beam to length should be in range 0.12 to 0.18, given range is 0.25-0.25. Using border value.
09:44:13 INFO opendrift.models.basemodel.environment:203: Adding a global landmask from GSHHG
09:44:18 INFO opendrift.models.basemodel.environment:227: Fallback values will be used for the following variables which have no readers:
09:44:18 INFO opendrift.models.basemodel.environment:230: sea_surface_wave_stokes_drift_x_velocity: 0.000000
09:44:18 INFO opendrift.models.basemodel.environment:230: sea_surface_wave_stokes_drift_y_velocity: 0.000000
09:44:18 INFO opendrift.models.basemodel.environment:230: sea_surface_wave_significant_height: 0.000000
09:44:18 INFO opendrift.models.basemodel.environment:230: sea_surface_wave_mean_period_from_variance_spectral_density_second_frequency_moment: 0.000000
Running model
o.run(steps=24, stop_on_error=True)
09:44:18 INFO opendrift:1814: Storing previous values of element property lon because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
09:44:18 INFO opendrift:1814: Storing previous values of element property lat because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
09:44:18 INFO opendrift:952: Using existing reader for land_binary_mask to move elements to ocean
09:44:18 INFO opendrift:982: All points are in ocean
09:44:18 INFO opendrift:2111: 2026-01-09 09:44:13.879271 - step 1 of 24 - 1000 active elements (0 deactivated)
09:44:18 INFO opendrift.readers:63: Opening file with xr.open_dataset
09:44:20 INFO opendrift.readers.reader_netCDF_CF_generic:332: Detected dimensions: {'x': 'x', 'y': 'y', 'time': 'time'}
09:44:20 INFO opendrift.readers:63: Opening file with xr.open_dataset
09:44:21 INFO opendrift.readers.reader_netCDF_CF_generic:332: Detected dimensions: {'time': 'time', 'x': 'x', 'y': 'y'}
09:44:21 INFO opendrift.readers:63: Opening file with xr.open_dataset
09:44:23 INFO opendrift.readers.reader_netCDF_CF_generic:332: Detected dimensions: {'y': 'rlat', 'x': 'rlon', 'time': 'time'}
09:44:25 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:25 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:26 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:26 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:28 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:28 INFO opendrift:2111: 2026-01-09 10:44:13.879271 - step 2 of 24 - 1000 active elements (0 deactivated)
09:44:29 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:29 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:30 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:30 INFO opendrift:2111: 2026-01-09 11:44:13.879271 - step 3 of 24 - 1000 active elements (0 deactivated)
09:44:32 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:32 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:33 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:33 INFO opendrift:2111: 2026-01-09 12:44:13.879271 - step 4 of 24 - 1000 active elements (0 deactivated)
09:44:34 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:34 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:34 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:34 INFO opendrift:2111: 2026-01-09 13:44:13.879271 - step 5 of 24 - 1000 active elements (0 deactivated)
09:44:37 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:37 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:38 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:38 INFO opendrift:2111: 2026-01-09 14:44:13.879271 - step 6 of 24 - 1000 active elements (0 deactivated)
09:44:40 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:40 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:41 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:41 INFO opendrift:2111: 2026-01-09 15:44:13.879271 - step 7 of 24 - 1000 active elements (0 deactivated)
09:44:43 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:43 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:44 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:44 INFO opendrift:2111: 2026-01-09 16:44:13.879271 - step 8 of 24 - 1000 active elements (0 deactivated)
09:44:46 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:46 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:46 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:46 INFO opendrift:2111: 2026-01-09 17:44:13.879271 - step 9 of 24 - 1000 active elements (0 deactivated)
09:44:48 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:48 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:49 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:49 INFO opendrift:2111: 2026-01-09 18:44:13.879271 - step 10 of 24 - 1000 active elements (0 deactivated)
09:44:51 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:51 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:52 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:52 INFO opendrift:2111: 2026-01-09 19:44:13.879271 - step 11 of 24 - 1000 active elements (0 deactivated)
09:44:54 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:54 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:55 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:55 INFO opendrift:2111: 2026-01-09 20:44:13.879271 - step 12 of 24 - 1000 active elements (0 deactivated)
09:44:57 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:57 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:44:57 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:44:57 INFO opendrift:2111: 2026-01-09 21:44:13.879271 - step 13 of 24 - 1000 active elements (0 deactivated)
09:45:00 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:00 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:00 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:00 INFO opendrift:2111: 2026-01-09 22:44:13.879271 - step 14 of 24 - 1000 active elements (0 deactivated)
09:45:02 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:02 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:03 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:03 INFO opendrift:2111: 2026-01-09 23:44:13.879271 - step 15 of 24 - 1000 active elements (0 deactivated)
09:45:05 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:05 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:06 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:06 INFO opendrift:2111: 2026-01-10 00:44:13.879271 - step 16 of 24 - 1000 active elements (0 deactivated)
09:45:10 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:10 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:10 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:10 INFO opendrift:2111: 2026-01-10 01:44:13.879271 - step 17 of 24 - 1000 active elements (0 deactivated)
09:45:18 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:18 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:19 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:19 INFO opendrift:2111: 2026-01-10 02:44:13.879271 - step 18 of 24 - 1000 active elements (0 deactivated)
09:45:24 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:24 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:26 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:26 INFO opendrift:2111: 2026-01-10 03:44:13.879271 - step 19 of 24 - 1000 active elements (0 deactivated)
09:45:32 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:32 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:32 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:32 INFO opendrift:2111: 2026-01-10 04:44:13.879271 - step 20 of 24 - 1000 active elements (0 deactivated)
09:45:36 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:36 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:37 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:37 INFO opendrift:2111: 2026-01-10 05:44:13.879271 - step 21 of 24 - 1000 active elements (0 deactivated)
09:45:39 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:39 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:40 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:40 INFO opendrift:2111: 2026-01-10 06:44:13.879271 - step 22 of 24 - 1000 active elements (0 deactivated)
09:45:42 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:42 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:43 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:43 INFO opendrift:2111: 2026-01-10 07:44:13.879271 - step 23 of 24 - 1000 active elements (0 deactivated)
09:45:45 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:45 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:46 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
09:45:46 INFO opendrift:2111: 2026-01-10 08:44:13.879271 - step 24 of 24 - 1000 active elements (0 deactivated)
09:45:48 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:48 WARNING opendrift.readers.interpolation.structured:63: Ensemble data currently not extrapolated towards seafloor
09:45:49 INFO opendrift.models.shipdrift:311: Using Stokes drift direction as wave direction
Print and plot results
print(o)
o.plot(linecolor='orientation')
#o.animation(color='orientation', markersize=20, filename="orientation.gif", legend=['left','right'],colorbar=False,cmap='bwr')
o.animation(color='orientation', legend=['left','right'], markersize=20, colorbar=False, cmap='bwr')
===========================
--------------------
Reader performance:
--------------------
global_landmask
0:00:00.0 total
0:00:00.0 preparing
0:00:00.0 reading
0:00:00.0 masking
--------------------
https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml
0:00:18.3 total
0:00:00.0 preparing
0:00:18.3 reading
0:00:00.0 interpolation
0:00:00.0 interpolation_time
0:00:00.0 rotating vectors
0:00:00.0 masking
--------------------
https://thredds.met.no/thredds/dodsC/mepslatest/meps_lagged_6_h_latest_2_5km_latest.nc
0:00:47.5 total
0:00:00.0 preparing
0:00:47.5 reading
0:00:00.2 interpolation
0:00:00.0 interpolation_time
0:00:00.0 rotating vectors
0:00:00.0 masking
--------------------
https://thredds.met.no/thredds/dodsC/cmems/mywavewam3km/dataset-wam-arctic-1hr3km-be.ncml
0:00:18.6 total
0:00:00.0 preparing
0:00:18.5 reading
0:00:00.0 interpolation
0:00:00.0 interpolation_time
0:00:00.0 rotating vectors
0:00:00.0 masking
--------------------
Performance:
1:35.5 total time
4.5 configuration
0.0 preparing main loop
0.0 moving elements to ocean
1:31.0 main loop
0.4 updating elements
0.0 cleaning up
--------------------
===========================
Model: ShipDrift (OpenDrift version 1.14.7)
1000 active ShipObject particles (0 deactivated, 0 scheduled)
-------------------
Environment variables:
-----
land_binary_mask
1) global_landmask
-----
x_sea_water_velocity
y_sea_water_velocity
1) https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml
2) https://thredds.met.no/thredds/dodsC/cmems/mywavewam3km/dataset-wam-arctic-1hr3km-be.ncml
-----
x_wind
y_wind
1) https://thredds.met.no/thredds/dodsC/mepslatest/meps_lagged_6_h_latest_2_5km_latest.nc
-----
sea_surface_wave_mean_period_from_variance_spectral_density_second_frequency_moment
sea_surface_wave_significant_height
sea_surface_wave_stokes_drift_x_velocity
sea_surface_wave_stokes_drift_y_velocity
1) https://thredds.met.no/thredds/dodsC/cmems/mywavewam3km/dataset-wam-arctic-1hr3km-be.ncml
Discarded readers:
Time:
Start: 2026-01-09 09:44:13.879271 UTC
Present: 2026-01-10 09:44:13.879271 UTC
Calculation steps: 24 * 1:00:00 - total time: 1 day, 0:00:00
Output steps: 25 * 1:00:00
===========================
09:46:12 INFO opendrift:4660: Saving animation to /root/project/docs/source/gallery/animations/example_shipdrift_0.gif...
09:46:28 INFO opendrift:3094: Time to make animation: 0:00:16.471966
Total running time of the script: (2 minutes 22.143 seconds)